LaPierre Overvolt 5.4 HT chain jumping off

[Peps]

Hi there, I've been following @Rob Rides EMTB Youtube channel for a while and I just recently purchased a new Lapierre Overvolt 5.4 HT. It is a good bike and the only one I could find available three weeks ago even though I would have preferred a Bosh Gen 4 powered bike.

Anyway I'm having a problem with the chain jumping off from the front cog/crank every single time I'm jumping from 5 cm roots in the park!!! This is a bit extreme for an mtb I guess, never experienced something like that before. I'm just back from Tenerife where I spend the last 4 months renting all sorts of e-mtbs such as the brand new Specialised Levo SL, Connondale Habit Neo, 2 Haibike and others and never had a problem even jumping 1.5 m on rocky trails. Is that normal to have this problem with my Lapierre? I brought it to Pure Electric shop (where I bought it) for a check and everything looks good to the mechanic.
I bought this chain guide () which I've been reading it could be a solution to avoid the chain going off but it did't fit!
Do you think a chain guide would be a good solution? Also, does anyone know which model of chain guide would be compatible with my e-bike, because I could't find anything compatible! It has a Yamaha PW TE motor and this is the link to the bike: Overvolt HT 5.4 | 2021 | Lapierre Bikes

What do you guys think about this issue?

Many thanks in advance and I'm happy to have joined e-mtb forum!!

 

[Peps]

Does anyone have any idea if the chain jumping off just passing over a tree root is normal and how to potentially fix it?

 

[Mikerb]

Since it is a new bike it is more likely to be a set up problem than anything else. To answer your question, no the chain should not come off the chain wheel just because you went over a root.
Some things to investigate
1. Has the correct chain been fitted?
2. Is the chain the correct length?
3. Is the chain wheel loose?
4. Is the rear mech loose?
5 Is there any damage on the chain...or a stiff link?

The chain coming off the chain wheel is usually caused by either a slack chain, excessive wear on the chain wheel, a loose chain wheel, a badly aligned chain line. I am not familiar with your make of rear mech but I do not think it has a clutch and that makes having the correct chain length more critical, and a chain guide somewhat more advisable. Wear is unlikely since the bike is new, and chain line should not be critical given it is only a 9 speed cassette.

A photo like the one above but with the chain fully on the chain wheel may be useful to check chain length.

Does it make a difference what gear you are in when the chain slips off the chain wheel?

 

[Zimmerframe]

I think you have the Shimano Acera RDM3000GS 9s Shadow. Looking at it, it doesn't have a clutch - so there isn't much chain tension.

I had a hardtail with no clutch on the derailleur and the chain would come off every time you rode down anything bumpy, so I just swapped it out for an XT one.

So something with a clutch like this :

SHIMANO SHADOW RD | SHIMANO BIKE COMPONENT | SHIMANO BIKE-EU

To Build Closer Relationships between People, Nature, and Bicycles. We believe in the power of cycling to create a better world as we move forward. We inspire all people to enjoy our products in their everyday lives and where they take them.

bike.shimano.com

Your problem is that Shimano don't make a 9 speed with a clutch ..

I did read you can use a 10 speed SLX with a 4mm spacer, which gets the pull ratio close enough to work properly, but it's a bit of a bodge.

You could swap the cassette/shifter etc to deore spec 10 speed.

@Gary any ideas ?

 

[Peps]

Since it is a new bike it is more likely to be a set up problem than anything else. To answer your question, no the chain should not come off the chain wheel just because you went over a root.
Some things to investigate
1. Has the correct chain been fitted?
2. Is the chain the correct length?
3. Is the chain wheel loose?
4. Is the rear mech loose?
5 Is there any damage on the chain...or a stiff link?

The chain coming off the chain wheel is usually caused by either a slack chain, excessive wear on the chain wheel, a loose chain wheel, a badly aligned chain line. I am not familiar with your make of rear mech but I do not think it has a clutch and that makes having the correct chain length more critical, and a chain guide somewhat more advisable. Wear is unlikely since the bike is new, and chain line should not be critical given it is only a 9 speed cassette.

A photo like the one above but with the chain fully on the chain wheel may be useful to check chain length.

Does it make a difference what gear you are in when the chain slips off the chain wheel?

All your 5 questions are having a positive answer since I brought the bike to the shop for inspection last week and he said that the gearbox was slightly out of alignment and he fixed it. Also he run a safety check and everything is perfect so I guess it might be because of the lack of clutch as @Zimmerframe mentioned. While jumping from the root I was looking down to the chain and it was moving quite a lot coming from the gearbox so I guess it is because of the entry level part on the back after all?

 

[Gary]

Yeah. you have no clutch. 9 speed shimano mechs don't
what looks like a normal chainring (or not a particularly good narrow wide tooth design)
and your chain looks like it may be too long.

it's going to cost you a fair bit to sort it out.
Your cheapest option would be to buy a microshift 9 speed advent mech and shifter (advent has a clutch) and then you can keep your cassette and chain (shorten it though) and run a 104bcd narrow wide ring from Ebay. less than a tenner posted.

any other options would mean a whole new drivetrain or a whole lot of bodging

 

[Peps]

I think you have the Shimano Acera RDM3000GS 9s Shadow. Looking at it, it doesn't have a clutch - so there isn't much chain tension.

I had a hardtail with no clutch on the derailleur and the chain would come off every time you rode down anything bumpy, so I just swapped it out for an XT one.

So something with a clutch like this :

SHIMANO SHADOW RD | SHIMANO BIKE COMPONENT | SHIMANO BIKE-EU

To Build Closer Relationships between People, Nature, and Bicycles. We believe in the power of cycling to create a better world as we move forward. We inspire all people to enjoy our products in their everyday lives and where they take them.

bike.shimano.com

Your problem is that Shimano don't make a 9 speed with a clutch ..

I did read you can use a 10 speed SLX with a 4mm spacer, which gets the pull ratio close enough to work properly, but it's a bit of a bodge.

You could swap the cassette/shifter etc to deore spec 10 speed.

@Gary any ideas ?

How much do you think this swap might cost me? Do you know any reliable and skilled e-bike shop in SW London where I can take the bike to?

 

[Peps]

BTW I have another problem with this bike. I just came back from a 15 mins spin around my place (so only tarmac unfortunately) and again my motor (Yamaha PW TE) is switching off 2-3 times in a row with a 1 minute interval between one and another time and then is suddenly good and not turning off again. This is the third time that is happening after the bike has been sitting for 24h or more, the first time happened last week just the day before bringing the bike to the shop. They said that nothing popped up out of the diagnostic....but still a little bit extreme I'd say. Anyone having this issue so far? I covered 100 miles only so far

 

[Gary]

How much do you think this swap might cost me? Do you know any reliable and skilled e-bike shop in SW London where I can take the bike to?

You don't need an Ebike shop. any decent bike workshop/mechanic can fit the drivetrain parts for you. They're not specific to Ebikes.
Parts + £40 labour should cover it.

But with all the issues you're having with basically a brand new bike take it back to where you bought it.

 

[Peps]

You don't need an Ebike shop. any decent bike workshop/mechanic can fit the drivetrain parts for you. They're not specific to Ebikes.
Parts + £40 labour should cover it.

But with all the issues you're having with basically a brand new bike take it back to where you bought it.

Thank you so much @Gary I really appreciated it! I bought it from Pure Electric online and in general both online and in store i didn't receive a nice treatment...

 

[Jimbo Vills]

How much do you think this swap might cost me? Do you know any reliable and skilled e-bike shop in SW London where I can take the bike to?

Hey mate. Try energise in coulsdon, might not be a million miles from you. If you don’t take it back to purchase shop that is....

as said, don’t need to be e bike shop, but they are mega helpful and Lapierre dealers so should be more than Qualifies to assist ??

 

[lightning]

The chain shouldn't be falling off the front chain ring, take it back to the shop and ask them to sort it.

lf there's no other solution get them to install a chain device that fits.

 

[Peps]

Thank you guys for the tips! Today I managed to bring the bike to the shop, they checked and even after aligning one more time everything the mechanic got the chain off for a quick test ride around London bridge hence they accepted to refund me! Now though I have no bike!
Does anyone know when the new Decathlon Stylus will be available? That's the new target!

 

[lightning]

A clutch rear mech for £50 would probably have sorted it.
But if you didn't like the bike then l guess it's a case of putting your name down for the Decathlon one and waiting for stock to arrive.

 

[Peps]

A clutch rear mech for £50 would probably have sorted it.
But if you didn't like the bike then l guess it's a case of putting your name down for the Decathlon one and waiting for stock to arrive.

If it would have been only the drivetrain/ clutch missing I would have replaced it. Here the biggest problem was the motor switching off several times without anyone knowing why!

On the Decathlon Stilus does anyone have any insider news on when it will become available?

Thank you so much!

 

[lightning]

The motor issue is more serious. l can see why you went for a refund.

Decathlon Stilus expected "August/September" according to my local
store.
I suggest you register for stock alerts on their website and then you will get an email when it's in stock.
Price has gone up from £2795 to £3495